Altruism (or Ethical Altruism) is an ethical doctrine that holds that individuals have a moral obligation to help, serve or benefit others, if necessary at the sacrifice of self interest. More precisely, an action is morally right if the consequences of that action are more favourable than unfavourable to everyone except the agent.

The term "altruism" (initially derived from the Latin "alter" meaning "other") was coined by Auguste Comte, the French founder of Positivism, in order to describe his ethical doctrine, which he summed up in the phrase: "Live for others". In more general terms, Altruism is selfless concern for the welfare of others (although its common usage does not necessarily entail any ethical obligation).

Altruism is often seen as a form of Consequentialism, as it indicates that an action is ethically right if it brings good consequences to others. It may be seen as similar to Utilitarianism, although an essential difference is that Utilitarianism prescribes acts that maximize good consequences for all of society, while Altruism prescribes maximizing good consequences for everyone except the actor. It is the opposite of Egoism, which holds that individuals should do what is best for themselves, that it is not only their right but their duty to look after their own interests first.

Friedrich Nietzsche held that the idea that it is virtuous to treat others as more important than oneself is degrading and demeaning to the self, and hinders the individual's pursuit of self-development, excellence and creativity. He maintained that it was an ideology fabricated by the weak for the weak, and masks self-poisoning resentment about individual and collective powerlessness.

The ObjectivistAyn Rand (1905 - 1982) is on record as stating that most problems in the world come from the doctrine of Altruism, and argues that there is no rational ground for asserting that sacrificing yourself in order to serve others is morally superior to pursuing your own self-interest. Furthermore, if the state were to enforce Altruism as a moral ideal, this could ultimately result in the state forcing everyone into a collectivist political system.

Others have argued that actions formerly seen as altruistic are in reality just a form of enlightened self-interest.